Support design version 2 in the boot loader.

- cntr/fw/common/io.h (LED): define version-specific LED pins
- cntr/fw/common/io.h (PROBE_TERM): describe how the role differs between
  version 1 and 2
- cntr/fw/common/config.h (PLATFORM_ENTER, PLATFORM_EXIT): add the version
  2 LED

cntr/fw/common/config.h

@@ -35,16 +35,18 @@
  */
 
 #define PLATFORM_ENTER			\
-	LED_MODE |= 1 << LED_BIT;	\
-	XBR1 = XBARE;
+	LEDv1_MODE |= 1 << LEDv1_BIT;	\
+	LEDv2_MODE |= 1 << LEDv2_BIT;	\
+	XBR1 = XBARE
 
 
 /*
  * Turn off the LED when we exit the boot loader.
  */
 
-#define PLATFORM_EXIT \
-	LED = 0
+#define PLATFORM_EXIT	\
+	LEDv1 = 0;	\
+	LEDv2 = 0
 
 
 /* ----- Application configuration ----------------------------------------- */

cntr/fw/common/io.h

@@ -16,7 +16,8 @@
 
 /* Diagnostic LED */
 
-#define	LED	P1_3
+#define	LEDv1	P1_3
+#define	LEDv2	P2_2
 
 /* Probe input */
 
@@ -24,7 +25,12 @@
 #define	PROBE_ECI	P1_1
 #define	PROBE_INT0	P0_7
 
-/* Probe termination */
+/*
+ * Probe termination
+ *
+ * - v1: 100 kOhm termination (not very useful)
+ * - v2: pull-up for input amplifier
+ */
 
 #define	PROBE_TERM	P1_2